Power
There are many kinds of forklifts that are operated by propane gas. Forklifts that utilize propane are easy to refill. The gas is stored in a pressurized tank on the truck's rear. The propane is pushed into the engine, where it is converted into vapor and the vapor mixes with air. The throttle of the forklift is utilized to be able to control the flow of vapor. A spark plug ignites the mixture of air and vapor producing pressure that moves the pistons. The pistons power the hydraulic pump and turn the wheels.
Since the types of forklifts which are powered by propane have low emissions and are clean burning, they are best to be used in warehouses and other buildings.
Hydraulics
What enables a forklift to lift and transport heavy things from one location to another is the hydraulic system. Cylinders, a pump and tubes make up the hydraulic system. The pump forces dense fluid in the tubing and into the cylinders. The pressure build up pushes a piston, that raises the forks. When the forks are lowered by the operator, the hydraulic fluid flows out of the cylinders and back in the pump.
Steering
Propane forklifts work well where maneuverability is necessary. Unlike an automobile, a forklift makes use of its back wheels to pivot, that enables the forklift to rapidly turn on a tight radius.